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particle physics

Reaching for the Multiverse
Infinity and Beyond: The Ultimate Test

Multiverse Collisions May Dot the Sky

Early in cosmic history, our universe may have bumped into another — a primordial clash that could have left traces in the Big Bang’s afterglow.

Infinity and Beyond: The Ultimate Test

In a Multiverse, What Are the Odds?

Testing the multiverse hypothesis requires measuring whether our universe is statistically typical among the infinite variety of universes. But infinity does a number on statistics.


Dwarf Galaxies Dim Hopes of Dark Matter

For five years physicists have been tantalized by possible evidence of dark matter in the Milky Way’s center. But new results from small satellite galaxies have complicated the story.

particle physics

Quark Quartet Fuels Quantum Feud

Newly discovered particles are forcing physicists to extend their simple picture of subatomic interactions or replace it with a more nuanced understanding.

theoretical physics

At Multiverse Impasse, a New Theory of Scale

Physicists have begun to explore the idea that mass and length may not be fundamental properties of nature. The hypothesis could help to avoid the conclusion that our world is just a weird bubble in an endlessly foaming multiverse.

Boucing droplet
quantum mechanics

Fluid Tests Hint at Concrete Quantum Reality

Surprising oil drop experiments suggest that the quantum world may not be as strange as advertised.

Efimov trimers.

Physicists Prove Surprising Rule of Threes

Three groups of experimentalists have independently observed a strange state of matter that forms from three particles of any type and at any scale, from practically infinitesimal to infinite.

theoretical physics

Betting on the Future of Quantum Gravity

New calculations suggest physicists may someday discover a fundamental theory of gravity, but it could require a radical new perspective on the universe.

Gamma Ray Excess

Case for Dark Matter Signal Strengthens

A new analysis strengthens the case that gamma rays emanating from the center of the Milky Way come from dark matter particles known as WIMPs.